1. Field of the Invention
The present invention relates to a developer supply device and, more particularly to a sliding cover device arrangement for controlling toner passage between the toner container and developing device of an image forming apparatus, for example, an electrophotographic copying machine, an electrophotographic printer, an electrophotographic facsimile, an electrophotographic word processor, or the like.
2. Description of the Related Art
A regular process cartridge for an image forming apparatus is generally comprised of an electrophotographic photosensitive member, developing means, charging means, cleaning means, and a toner container. When the toner container is used up, the whole assemble of the process cartridge becomes useless and must be thrown away. It is not economical to throw the whole assembly of the process cartridge away after the process cartridge is emptied. Further, the waste process cartridge may cause pollution to the environment if it is not disposed of in a proper manner.
The present invention has been accomplished to eliminate the aforesaid drawbacks. In one aspect, the present invention relates to a sliding cover device arrangement for controlling toner passage between the toner container and the developing device of an image forming apparatus, which enables the user to replace the toner container without throwing the whole assembly of the process cartridge away when the toner of the toner container is depleted. In one embodiment of the present invention, the sliding cover device arrangement includes a developing device having a plurality of toner receiving openings and a first sliding cover adapted for closing and opening the toner receiving openings, a toner container having a plurality of toner supplying openings corresponding to the toner receiving openings and a second sliding cover adapted for closing and opening the toner supplying openings, and coupling means formed on the developing device and the toner device for enabling the first sliding cover and the second sliding cover to be moved to close and open the toner supplying openings and the toner receiving openings synchronously. The coupling means includes projection means and recess means for engagement with the projection means. According to another embodiment of the present invention, the projection means comprises a plurality of projections protruded from the second sliding cover of the toner container, each projection extended around a corresponding one of the plurality of openings of the second sliding cover and respectively engaged by the toner receiving openings of the developing device.